Overheating?
Thread Starter
Racer
Joined: Apr 2013
Posts: 321
Likes: 55
From: Knoxville TN
Overheating?
Lat night coming home from dinner all of the sudden the car shut the AC off and a warning came up that the car was too hot. Weird thing is the temp gauge went to "0" instead of showing the actual temp. I shut it down and checked under the hood. There was plenty of fluid in the overflow, maybe a 1/4 inch from the top full. I let it cool and started it again and all was well. The temp rarely gets over 190 or so which I don't think is particularly hot.
I have had a coolant level warning come up before and I've brought it to the dealer. They couldn't find anything wrong and topped off the fluid. Then its fine for a month or so then shows up again.
Is this car that sensitive to the coolant level?
I have had a coolant level warning come up before and I've brought it to the dealer. They couldn't find anything wrong and topped off the fluid. Then its fine for a month or so then shows up again.
Is this car that sensitive to the coolant level?
Burning Brakes
Joined: Sep 2014
Posts: 912
Likes: 52
From: Mech. pa
When the car is running observe the coolant level. Is it surging? If so it may be head gasket issue. Yes the coolant level is sensitive. Have a pressure test done. use an infrared temp. device to look for: thermostat operation, inlet and outlet temp of rad,Verify fan operation. To lower engine temp turn heat up full and fan on high, this my get you home safely
Team Owner
Joined: Aug 2006
Posts: 25,105
Likes: 3,156
C6 of Year Finalist (appearance mods) 2019
Check your radiator for blockage. Plastic bags easily get sucked up and block air flow. Flush radiator once a year.
I made a wand out of 3/8 soft copper, end crimped with 2 small holes drilled in it. Do a search there is a good thread about how to make one.
Need to do mine again before the summer heat.
I made a wand out of 3/8 soft copper, end crimped with 2 small holes drilled in it. Do a search there is a good thread about how to make one.
Need to do mine again before the summer heat.
Thread Starter
Racer
Joined: Apr 2013
Posts: 321
Likes: 55
From: Knoxville TN
I'll look at blockage first but my thought is its a sensor as has been suggested because it really doesn't run hot and only shows up during short bursts of acceleration where you have to slow down quickly or short bursts of high revs in traffic. So where the temp rises quickly but doesn't necessarily get hot.
Team Owner
Joined: Jun 2005
Posts: 46,295
Likes: 2,596
From: Northern, VA
St. Jude Donor '15
"In honor of jpee"
"There was plenty of fluid in the overflow, maybe a 1/4 inch from the top full."
If that is true above, something IS going on. A quarter inch from the top of the tank means (to me) there is too much fluid in the overflow tank. It shouldn't be that high ever, hot or cold. The normal cold (early morning before you start car) is supposed to be somewhere betw. the hot and cold line on the outside of the tank, usually around midpoint.
Again, if the level hot is what you say, for whatever reason, the water pump is pushing fluid out of the engine and into the overflow--and it is not returning to the engine to cool---which means to me that the engine may actually be running low on fluid (slightly, but maybe enough to trigger a warning). To me, this could be several things but the only things I can think of are water pump or thermostat---or some sort of clog or lack of power fr. the pump.
You don't state year of car, miles, or last time rad fluid was changed, so it's difficult to comment on it from that standpoint. More info would help. Also, any mods to the engine of any kind incld. a tune, headers, etc.? Finally, when the engine temp starts to rise, does the FAN come on?
If that is true above, something IS going on. A quarter inch from the top of the tank means (to me) there is too much fluid in the overflow tank. It shouldn't be that high ever, hot or cold. The normal cold (early morning before you start car) is supposed to be somewhere betw. the hot and cold line on the outside of the tank, usually around midpoint.
Again, if the level hot is what you say, for whatever reason, the water pump is pushing fluid out of the engine and into the overflow--and it is not returning to the engine to cool---which means to me that the engine may actually be running low on fluid (slightly, but maybe enough to trigger a warning). To me, this could be several things but the only things I can think of are water pump or thermostat---or some sort of clog or lack of power fr. the pump.
You don't state year of car, miles, or last time rad fluid was changed, so it's difficult to comment on it from that standpoint. More info would help. Also, any mods to the engine of any kind incld. a tune, headers, etc.? Finally, when the engine temp starts to rise, does the FAN come on?
Last edited by AORoads; May 6, 2015 at 01:07 PM. Reason: Brainus-interruptus
Race Director
Joined: Oct 2010
Posts: 14,475
Likes: 785
From: Las Vegas NV
"There was plenty of fluid in the overflow, maybe a 1/4 inch from the top full."
If that is true above, something IS going on. A quarter inch from the top of the tank means (to me) there is too much fluid in the overflow tank. It shouldn't be that high ever, hot or cold. The normal cold (early morning before you start car) is supposed to be somewhere betw. the hot and cold line on the outside of the tank, usually around midpoint.
Again, if the level hot is what you say, for whatever reason, the water pump is pushing fluid out of the engine and into the overflow--and it is not returning to the engine to cool---which means to me that the engine may actually be running low on fluid (slightly, but maybe enough to trigger a warning). To me, this could be several things but the only things I can think of are water pump or thermostat---or some sort of clog or lack of power fr. the pump.
You don't state year of car, miles, or last time rad fluid was changed, so it's difficult to comment on it from that standpoint. More info would help. Also, any mods to the engine of any kind incld. a tune, headers, etc.? Finally, when the engine temp starts to rise, do the fans come on, both of them?
If that is true above, something IS going on. A quarter inch from the top of the tank means (to me) there is too much fluid in the overflow tank. It shouldn't be that high ever, hot or cold. The normal cold (early morning before you start car) is supposed to be somewhere betw. the hot and cold line on the outside of the tank, usually around midpoint.
Again, if the level hot is what you say, for whatever reason, the water pump is pushing fluid out of the engine and into the overflow--and it is not returning to the engine to cool---which means to me that the engine may actually be running low on fluid (slightly, but maybe enough to trigger a warning). To me, this could be several things but the only things I can think of are water pump or thermostat---or some sort of clog or lack of power fr. the pump.
You don't state year of car, miles, or last time rad fluid was changed, so it's difficult to comment on it from that standpoint. More info would help. Also, any mods to the engine of any kind incld. a tune, headers, etc.? Finally, when the engine temp starts to rise, do the fans come on, both of them?
Oh, and BTW, there's only one fan.
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One fan, OP. 
Thread Starter
Racer
Joined: Apr 2013
Posts: 321
Likes: 55
From: Knoxville TN
"There was plenty of fluid in the overflow, maybe a 1/4 inch from the top full."
If that is true above, something IS going on. A quarter inch from the top of the tank means (to me) there is too much fluid in the overflow tank. It shouldn't be that high ever, hot or cold. The normal cold (early morning before you start car) is supposed to be somewhere betw. the hot and cold line on the outside of the tank, usually around midpoint.
Again, if the level hot is what you say, for whatever reason, the water pump is pushing fluid out of the engine and into the overflow--and it is not returning to the engine to cool---which means to me that the engine may actually be running low on fluid (slightly, but maybe enough to trigger a warning). To me, this could be several things but the only things I can think of are water pump or thermostat---or some sort of clog or lack of power fr. the pump.
You don't state year of car, miles, or last time rad fluid was changed, so it's difficult to comment on it from that standpoint. More info would help. Also, any mods to the engine of any kind incld. a tune, headers, etc.? Finally, when the engine temp starts to rise, does the FAN come on?
If that is true above, something IS going on. A quarter inch from the top of the tank means (to me) there is too much fluid in the overflow tank. It shouldn't be that high ever, hot or cold. The normal cold (early morning before you start car) is supposed to be somewhere betw. the hot and cold line on the outside of the tank, usually around midpoint.
Again, if the level hot is what you say, for whatever reason, the water pump is pushing fluid out of the engine and into the overflow--and it is not returning to the engine to cool---which means to me that the engine may actually be running low on fluid (slightly, but maybe enough to trigger a warning). To me, this could be several things but the only things I can think of are water pump or thermostat---or some sort of clog or lack of power fr. the pump.
You don't state year of car, miles, or last time rad fluid was changed, so it's difficult to comment on it from that standpoint. More info would help. Also, any mods to the engine of any kind incld. a tune, headers, etc.? Finally, when the engine temp starts to rise, does the FAN come on?
Team Owner
Joined: Sep 2000
Posts: 25,002
Likes: 2,703
From: Far NW 'burbs of Chicago
St. Jude Donor '13
The proper coolant level on the overflow tank is a line molded into the outside of the tank on the front, where no one ever sees it. On our 2006 and now 2009 it's marked "Full Cold", and there doesn't seem to be any indication for correct level when hot.
But when fully warmed up, the level is fairly close to the top of the tank.
Being on the front of the tank, the indication is effected by any nose up or down incline.
But when fully warmed up, the level is fairly close to the top of the tank.
Being on the front of the tank, the indication is effected by any nose up or down incline.
Thread Starter
Racer
Joined: Apr 2013
Posts: 321
Likes: 55
From: Knoxville TN
Just got it back from the dealer. New thermostat and new sensor. Also did a coolant flush. $470.00 later she's good as new. Curiously there was another '09 in for the same exact thing.
They did the Catalytic converter swap at the same time. So she's up to date.
Thanks for all your feedback guys.
They did the Catalytic converter swap at the same time. So she's up to date.
Thanks for all your feedback guys.